Engine starter



July 10. 1956 M. L. JACOBS ETAL 2,753,719

ENGINE STARTER Filed May 25, 1954 2 Sheets-Sheet 1 FIEZ INVENTOR. MMa-zws L Iicaas BY JasEP/l b! JZcoas JfroRMEI-f United States Patent ENGINE STARTER Marcellus L. Jacobs, Osseo, and Joseph H. Jacobs, Excelsior, Minn.

Application May 25, 1954, Serial No. 432,248

10 Claims. (Cl. 74-6) This invention has relation to engine starters and more particularly to electrically operated starters used to start engines which are connected to other equipment by pulleys and belt drive.

In a device made according to the present invention, a starter motor and a starter motor drive pulley are pivotally mounted with respect to a drive belt connecting an engine to be started to other equipment. The axis of the pivot about which the motor and starter drive pulley are mounted is parallel to the axis of the starter drive pulley and is spaced therefrom so that when the motor and pulley are swung on this pivot, the pulley is caused to move into contact with the drive belt from the engine. Movement of the motor and pulley toward the drive belt also causes the electrical circuit to the motor to be energized so that the motor will rotate. Rotation of the drive pulley as a result of rotation of the starter motor is in such a direction that when the pulley comes into contact with the drive belt, the friction of the pulley on the belt will cause the pulley to tend to walk up the belt in such a direction that the motor and pulley tend to continue to pivot on the axis of the pivot. This action will hold the pulley down against the belt and will cause the belt to be moved along past the pulley to turn over the engine. When the engine starts, the drive belt will move faster than the periphery of the starter pulley with which it is in contact and the frictional force holding the pulley against the belt will no longer be present. Spring means will then lift the motor and drive pulley away from the belt. As. this happens, the electrical circuit including the motor will open and the motor will cease to operate.

While the specification and drawings disclose the starter drive pulley operating on a V-belt in conjunction with the starting of a diesel engine, it is obvious that the same principle could be applied to a number of other types of belt, chain or gear drives and in conjunction with many other engine types.

In the drawings, 7

Fig. 1 is a top plan view of the device of the present invention in place on a base showing its relationship to' a diesel engine and an electric generator;

Fig. 2 is a vertical sectional view taken on the line 2--2 in Fig. 1;

Fig. 3 is a side elevational view of the device and of the engine and generator associated therewith as seen from the left in Fig. 1;

Fig. 4 is an enlarged fragmentary side elevational view of the device and the engine and generator as seen from the right in Fig. l with parts in section and parts broken away disclosing the relative positioning of the parts when the starter is in operation; and

Fig. 5 is a fragmentary side elevational view as in Fig. 4 but disclosing the relative positioning of the parts when the starter is inoperative.

Referring to the drawings and the numerals of reference thereon, a diesel engine and an electric generator 11 are mounted on a base 12. Engine drive pulleys 13 and generator driven pulleys 14 are operably connected ice to each other by the V-belts 15. In normal operation, after the engine is started, engine drive pulleys 13 will be driven by the engine and will in turn drive the driven pulleys 14 through the instrumentality of the V-belts 15.

A starter support bracket 16 is bolted to the base 12 through the instrumentality of bolts 17. An electric starter switch 18 of any usual or preferred construction is supported on an upwardly and outwardly extending ear of the starter support bracket 16. A pair of binding posts 19, 19 on the support bracket 16 are each electrically connected to separate parts of the starter switch 18.

A shaft 20 is rotatably mounted in the starter support bracket 16 and has a counter balanced starter handle 21, a cam 22 and a starter motor 23 fixedly mounted thereon. The cam 22 encompasses the shaft 20 and is generally concentric therewith while the starter motor is mounted on the shaft in such a manner that the axis of the motor is parallel to and spaced from the axis of the shaft. Starter drive pulleys 24 are fixably mounted with respect to the starter motor shaft. Collars 25 and 26 are mounted on the shaft 20 and are fastened thereto through the instrumentalities of the set screws 27 and 28, respectively. These collars are each designed to come in contact with one of a pair of upstanding ends of the starter support bracket 16 which serve as bearings for slideably and rotatably supporting the shaft 20. These collars determine the longitudinal positioning of the shaft and all of the parts connected thereto. When the engine starter is first installed in relationship to the engine, the set screws 27 and 28 are used to position the collars 25 and 26 on the shafts 20 so that the starter drive pulleys 24 will be in exact alinement with the engine drive pulleys 13 and the driven pulleys 14.

An arm 29 is integral with and extends radially outwardly from the collar 26. A strap 30 is fixably mounted on the base 12 as at 31. A limit rod 32 is pivotally mounted in the arm 29 as at 33 and is slidable through the strap 30 as at 34. Lock nuts 35 are connected to said limit rod and serve to limit the slideable movement of the limit rod with respect to the strap 30 in direction toward the arm 29. A compression coil spring 36 encompasses the limit rod 32 and presses against the arm 29 and the strap 30 to tend to cause the shaft 20 to rotate in clockwise direction as seen in Fig. 3 and in counterclockwise direction as seen in Figs. 4 and 5.

The electrical circuit of the starter includes batteries 37, a power cable 38 from the batteries to the starter motor 23, a cable 39 from the motor 23 to one of the binding posts 19 of the switch 18, and a cable 40 from the other binding post 19 back to the batteries 27.

Cam 22 is in alinement with a starter button 42 of the starter switch 18 and the cam has a flat side thereof denoted 41.

Operation In operation, the starter handle 21 is depressed from the position as seen in dotted lines in Fig. 3 to position as seen in full lines in that figure. This causes the shaft 20, the cam 22 and the starter motor 23 to revolve or rotate about the axis of the shaft 20. Since when the starter is not in operation and parts thereof are positioned as seen in Fig. 5, the fiat side 41 of the cam 22 is immediately adjacent the starter button 42 and the contacts of the starter 18 are consequently not closed; rotation of cam 22 due to movement of the starter handle will cause the cylindrical portion of said cam to force the starter button 42 in upward direction to cause the contacts of the starter switch 18 to become closed.

This completes the starter motor electrical circuit to the batteries 37 and the starter drive pulleys 24 will 1 v begin to rotate in direction as indicated in Fig. 4.

Simultaneously with the beginning of this rotation of the starter drive pulleys 24, said pulleys will come in contact with the V-belts 15. Friction between the sides of the pulleys and the belts will tend to cause the pulleys to continue to revolve in a clockwise direction as seen in Fig. 4 around the shaft 20. This causes the pulleys 24 to make increasingly tighter contact with the belts. By reason of this contact and friction between the pulleys and the belts, the lower portion of the belts will be caused to move to the right as seen in Fig. 4 and the engine drive pulleys 15 and generator driven pulleys 14 will consequently be moved to rotate in counterclockwise direction as seen in that figure.

This action will continue and the engine will be constantly turned over until the electrical circuit to the starter motor is interrupted, the starter handle 21 is forced to its upward position to lift the drive pulleys out of contact with the V-belts, or until the engine starts up and begins to operate under its own power.

When the engine starts up, the engine drive pulleys 13 will be driven at a faster speed than they are driven by the action of the starter motor 23 and the starter drive pulleys 24. When this happens, the speed of the V-belts 15 past the starter drive pulleys 24, will be greater than the peripheral speed of said pulleys 24. The frictional force tending to hold the starter drive puileys in contact with the V-belts will then be removed and contact between the V-belts and these pulleys will tend to cause the starter drive pulleys to revolve around the shaft in counterclockwise direction as seen in Fig. 4. Compression coils spring 36 operating against the strap will force the arm 29 to move in direction to rotate the shaft to lift the starter motor and the starter drive pulleys to position spaced from V-belts 15. The strength of the spring 36 and the force exerted thereby will be such that the shaft will be held to position the parts as shown in Fig. 5 until such time as this spring is again overcome by manually depressing the starter handle. Lock nuts on limit rod 32 come in contact with strap 30 to limit the rotation of the shaft about its axis in counterclockwise direction as seen in Fig. 5. When the parts are so positioned, the flat side 41 of the cam 22 is again adjacent the starter button 42 of the starter switch 18 and the electrical circuit of the starter motor will be broken so that the starter motor will cease to operate.

Should it be desirable, a stop can be provided to limit the rotation of the shaft 20 in clockwise direction as seen in Figs. 4 and 5. If the parts are so positioned that the clockwise rotation of the shaft 2b as seen in Figs. 4 and 5. If the parts are so positioned that the clockwise rotation of the shaft 20 as seen in Fig. 4 is stopped to allow the parts to be positioned so that a straight line through the axis of a starter drive pulley such as 24 and the shaft 20 would be approximately perpendicular to a drive belt such as 15, it would be possible to utilize flat belt or chain belt drives in place of the V -belt herein disclosed. Also, a gear could be used in place of the drive belts 15 in conjunction with a pinion or the like used in place of starter drive pulleys 24. Still other combinations are possible within the scope and spirit of this specification and the claims which follow.

What is claimed is:

1. The combination with an engine, an engine drive pulley operably connected to said engine, and a continuous power transmitting strip operably connected to said drive pulley, of an engine starter comprising a starter motor, a starter drive pulley connected to said starter motor and in operating alinement with said continuous power transmitting strip, and means for supporting said starter drive pulley to revolve on a fixed radius about a first axis parallel to an axis of said engine drive pulley, said first axis being spaced from said strip at a distance not greater than the sum of said fixed radius plus the pitch radius of said starter drive pulley.

2. The combination with an engine, an engine drive pulley operably connected to said engine, a driven pulley, and a belt operably connecting said drive and driven pulleys, of an engine starter comprising a starter motor, a starter drive pulley operably connected to said starter motor and in operating alinement with said belt, and means for supporting said starter drive pulley to revolve on a fixed radius about a first axis parallel to an axis of said engine drive pulley, said first axis being spaced from said belt at a distance no greater than the sum of said fixed radius plus the pitch radius of said starter drive pulley.

3. The combination as specified in claim 2, and means for bringing said starter drive pulley into driving relationship with said belt.

4. The combination as specified in claim 3, and means for energizing said motor when said starter drive pulley is in driving relationship with said belt and for de-energizing said motor when said starter drive pulley is spaced from said belt.

5. The combination as specified in claim 2, means for revolving said starter drive pulley about said first axis to bring it into driving relationship with said belt, and means constantly urging said starter drive pulley to position spaced from said belt.

6. The combination as specified in claim 5, means for energizing said motor when said starter drive pulley is in driving relationship with said belt and for de-energizing said motor when said starter drive pulley is spaced from said belt.

7. The combination with a base, an engine mounted on said base, an engine drive pulley operably connected to said engine, a driven pulley, and a continuous belt operably connecting said drive and driven pulleys, of an engine starter comprising a supporting shaft rotatably mounted with respect to said base, a starter motor integrally connected to said supporting shaft, a starter motor shaft rotatably mounted with respect to said starter motor to have an axis thereof parallel to the axis of said supporting shaft and spaced therefrom, a starter drive pulley operably mounted on said motor shaft to be in alinement with said belt, the axis of said supporting shaft being spaced from said belt at a distance not greater than the sum of the distance between said shafts plus the pitch radius of said starter drive pulley, an electrical circuit for energizing said motor to cause said motor shaft to rotate to move a first portion of said starter drive pulley nearest said belt in a first direction, and means for rotating said supporting shaft to bring said starter drive pulley into operating contact with said belt at position spaced in said first direction from a line perpendicular to said first portion of said starter belt and passing through said supporting shaft axis.

8. The combination as specified in claim 7, said electrical circuit including a switch, means for closing said switch to complete said circuit when said starter drive pulley is in contact with said belt and for opening said switch to interrupt said circuit when the starter drive pulley is spaced from the belt.

9. The combination as specified in claim 7, and spring means constantly urging said starter drive pulley to position spaced from said belt.

10. The combination as specified in claim 9, said electrical circuit including a switch, and means for closing said switch to complete said circuit when said starter drive pulley is in contact with said belt and for opening said switch to interrupt said circuit when said starter drive pulley is spaced from said belt.

References Cited in the file of this patent UNITED STATES PATENTS 1,882,022 Leyvastre Oct. 11, 1932 2,522,503 Dodwell Sept. 19, 1950 2,585,313, Hart Feb. 12, 1952' 

